[Serializer] xml empty array encoding

soyuka · soyuka · commit be51e2cbfe27 · 2025-09-29T14:04:15.000+02:00
diff --git a/src/Symfony/Component/Serializer/Encoder/XmlEncoder.php b/src/Symfony/Component/Serializer/Encoder/XmlEncoder.php
@@ -378,7 +378,7 @@ private function buildXml(\DOMNode $parentNode, mixed $data, string $format, arr
                     }
                 } elseif (\is_array($data) && !is_numeric($key)) {
                     // Is this array fully numeric keys?
-                    if (!$preserveNumericKeys && null === array_find_key($data, static fn ($v, $k) => is_string($k))) {
+                    if (!$preserveNumericKeys && $data && null === array_find_key($data, static fn ($v, $k) => \is_string($k))) {
                         /*
                          * Create nodes to append to $parentNode based on the $key of this array
                          * Produces <xml><item>0</item><item>1</item></xml>
diff --git a/src/Symfony/Component/Serializer/Tests/Encoder/XmlEncoderTest.php b/src/Symfony/Component/Serializer/Tests/Encoder/XmlEncoderTest.php
@@ -1069,12 +1069,24 @@ public function testDecodeArrayAsItem()
             </response>
             XML;
         $expected = ['person' => [
-            ['@key' => 0, 'firstname' => 'Benjamin', 'lastname' => 'Alexandre', ],
-            ['@key' => 1, 'firstname' => 'Damien', 'lastname' => 'Clay', ],
+            ['@key' => 0, 'firstname' => 'Benjamin', 'lastname' => 'Alexandre'],
+            ['@key' => 1, 'firstname' => 'Damien', 'lastname' => 'Clay'],
         ]];
 
         $this->assertSame($expected, $this->encoder->decode($source, 'xml', [
             XmlEncoder::PRESERVE_NUMERIC_KEYS => true,
         ]));
     }
+
+    public function testEncodeEmptyArrayWithoutPreservingKeys()
+    {
+        $source = ['person' => []];
+        $expected = <<<'XML'
+            <?xml version="1.0"?>
+            <response><person/></response>
+
+            XML;
+
+        $this->assertSame($expected, $this->encoder->encode($source, 'xml'));
+    }
 }

Original file line number	Diff line number	Diff line change
`@@ -378,7 +378,7 @@ private function buildXml(\DOMNode $parentNode, mixed $data, string $format, arr`
`378`	`378`	`}`
`379`	`379`	`} elseif (\is_array($data) && !is_numeric($key)) {`
`380`	`380`	`// Is this array fully numeric keys?`
`381`		`- if (!$preserveNumericKeys && null === array_find_key($data, static fn ($v, $k) => is_string($k))) {`
	`381`	`+ if (!$preserveNumericKeys && $data && null === array_find_key($data, static fn ($v, $k) => \is_string($k))) {`
`382`	`382`	`/*`
`383`	`383`	`* Create nodes to append to $parentNode based on the $key of this array`
`384`	`384`	`* Produces <xml><item>0</item><item>1</item></xml>`